de.unibonn.iai.eis.luzzu.io.helper

Class StreamMetadataSniffer

java.lang.Object

de.unibonn.iai.eis.luzzu.io.helper.StreamMetadataSniffer

public class StreamMetadataSniffer
extends Object

Author:

Jeremy Debattista This class acts as a helper class to the StreamProcessor to extract the available quality metadata from the assessed dataset. The output of this builder will be cached for future use.

Field Summary

Fields

Modifier and Type

Field and Description

int

counter Takes quad and tries to build the quality metadata with the quad information available The approach taken to build the temporary graph object is a poor man's approach, keeping in mind the following: 1) If the passed quad contains the triple "?x a DAQ.QualityGraph" then be can create a new TemporaryGraphMetadataCacheObject with the subject resource as the Graph URI 2) Since a quad might contain the GRAPH URI in its fourth (context) element, then: a) first check if the TemporaryGraphMetadataCacheObject is created and if so, check if the context element (in the quad) is the same as defined as the Graph URI of the java object.

Constructor Summary

Constructors

Constructor and Description
StreamMetadataSniffer()

Method Summary

Modifier and Type	Method and Description
de.unibonn.iai.eis.luzzu.cache.impl.TemporaryGraphMetadataCacheObject	getCachingObject()
void	sniff(com.hp.hpl.jena.sparql.core.Quad quad)

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

counter

public int counter

Takes quad and tries to build the quality metadata with the quad information available The approach taken to build the temporary graph object is a poor man's approach, keeping in mind the following: 1) If the passed quad contains the triple "?x a DAQ.QualityGraph" then be can create a new TemporaryGraphMetadataCacheObject with the subject resource as the Graph URI 2) Since a quad might contain the GRAPH URI in its fourth (context) element, then: a) first check if the TemporaryGraphMetadataCacheObject is created and if so, check if the context element (in the quad) is the same as defined as the Graph URI of the java object. If these are the same, then it is easy, as we just add the triples to the cached metadata. b) if the cached object is not created yet, then we create a temporary jena model containing all resources of the same graph (these are known when quads are streamed) and then stored in a hashmap. This hashmap will be used for building the final cached object, pushing the corresponding model from the datastructure to the cached object.

Constructor Detail

StreamMetadataSniffer

public StreamMetadataSniffer()

Method Detail

sniff

public void sniff(com.hp.hpl.jena.sparql.core.Quad quad)

getCachingObject

public de.unibonn.iai.eis.luzzu.cache.impl.TemporaryGraphMetadataCacheObject getCachingObject()

Returns:

Returns the Object to be Cached